What is protein? How much protein do we need? Is it possible to eat too much protein?

Protein is one of the basic building blocks of the human body, being about 16 percent of our total body weight. Muscle, hair, skin, and connective tissue are mainly made up of protein. However, protein plays a major role in all of the cells and most of the fluids in our bodies. In addition, many of our bodies' important chemicals -- enzymes, hormones, neurotransmitters, and even our DNA -- are at least partially made up of protein. Although our bodies are good at “recycling” protein, we use up protein constantly, so it is important to continually replace it.

Proteins are made up of smaller units called amino acids. Our bodies cannot manufacture the nine Essential Amino Acids, so it is important to include all of these amino acids in our diets through varied sources. Animal proteins such as meat, eggs, and dairy products have all of the Essential Amino Acids, and many plants have some of them.  Multi-Source Protein Blend Supplements can also be very helpful..

How much protein do we need?

Our protein needs depend on our age, size, and activity level. The standard method used by nutritionists to estimate our minimum daily protein requirement is to multiply the body weight in kilograms by .8, or weight in pounds by .37. This is the number of grams of protein that should be the daily minimum. According to this method, a person weighing 150 lbs. should eat 55 grams of protein per day, a 200-pound person should get 74 grams, and a 250-pound person, 92 grams.  Note: these are MINIMUM REQUIREMENTS for survival. 

For persons who are active, engage in routine workout or excersize, or who are striving to increase muscle, protein requirements will be much greater - AT LEAST 1 gram of protein per day for every pound of lean body mass, as a general rule.  This method is discussed in the Zone Diet and Protein Power books. Learn About This Method 

Do people who exercise need more protein?

Although it is controversial, there is evidence that people engaging in endurance exercise (such as long distance running) or heavy resistive exercise (such as body building) can benefit from additional protein in their diets, as noted above.

What happens if we don’t eat enough protein?

Unlike fat and glucose, our body has little capacity to store protein. If we were to stop eating protein, our body would start to break down muscle for its needs within a day or so. This means we would begin losing our lean body composition, or the desired composition, which is generally not a good thing.

Is it OK to eat a lot more protein than the minimum recommendations?

This is the crucial question for people on diets which are higher in protein than usual, as low-carb diets tend to be. In a review of the research, the National Academy of Sciences reported that the only known danger from high protein diets is for individuals with kidney disease. After careful study, they recommend that 10 percent to 35 percent of daily calories come from protein. They point out that increased protein could be helpful in treating obesity.

There is also accumulating evidence that extra protein may help prevent osteoporosis.  Extra protein can be broken down into glucose in a process called gluconeogenesis. On low carb diets, this happens continually. One benefit of obtaining glucose from protein is that it is absorbed into the bloodstream very slowly, so it doesn’t cause a rapid blood sugar increase and therefore has less potential for storage in the body's fat cells.

What foods have the most protein?

Meat, fish, eggs, dairy products, legumes, and nuts all have substantial amounts of protein.  Protein supplements can also be very useful.